With his striking beard and starched uniform, former Surgeon General C. Everett Koop became one of the most recognizable figures of the Reagan era — and one of the most unexpectedly enduring.

NEW YORK Dr. C. Everett Koop has long been regarded as the nation's doctor even though it has been nearly a quarter-century since he was surgeon general.

Koop, who died Monday at his home in Hanover, N.H., at age 96, was by far the best known and most influential person to carry that title. Koop, a 6-foot-1 evangelical Presbyterian with a biblical prophet's beard, donned a public health uniform in the early 1980s and became an enduring, science-based national spokesman on health issues.

He served for eight years during the Reagan administration and was a breed apart from his political bosses. He thundered about the evils of tobacco companies during a multiyear campaign to drive down smoking rates, and he became the government's spokesman on AIDS when it was still considered a "gay disease" by much of the public.

"He really changed the national conversation, and he showed real courage in pursuing the duties of his job," said Chris Collins, a vice president of amfAR, the Foundation for AIDS Research.

Even before that, he had been a leading figure in medicine. He was one of the first U.S. doctors to specialize in pediatric surgery at a time when children with complicated conditions were often simply written off as untreatable. In the 1950s, he drew national headlines for innovative surgeries such as separating conjoined twins.

His medical heroics are well noted, but he may be better remembered for transforming from a pariah in the eyes of the public health community into a remarkable servant who elevated the influence of the surgeon general if only temporarily.

"He set the bar high for all who followed in his footsteps," said Dr. Richard Carmona, who served as surgeon general a decade later under President George W. Bush.

Koop's religious beliefs grew after the 1968 death of his son David in a mountain-climbing accident, and he became an outspoken opponent of abortion. His activism is what brought him to the attention of the administration of President Ronald Reagan, who decided to nominate him for surgeon general in 1981. Though once a position with real power, surgeon generals had been stripped of most of their responsibilities in the 1960s.

By the time Koop got the job, the position was kind of a glorified health educator.

But Koop ran with it. One of his early steps involved the admiral's uniform that is bestowed to the surgeon general but that Koop's predecessors had worn only on ceremonial occasions. In his first year in the post, Koop stopped wearing his trademark bowties and suit jackets and instead began wearing the uniform, seeing it as a way to raise the visual prestige of the office.

In those military suits, he surprised the officials who had appointed him by setting aside his religious beliefs and feelings about abortion and instead waging a series of science-based public health crusades.

He was arguably most effective on smoking. He issued a series of reports that detailed the dangers of tobacco smoke, and in speeches began calling for a smoke-free society by the year 2000. He didn't get his wish, but smoking rates did drop from 38 percent to 27 percent while he was in office a huge decline.

Koop led other groundbreaking initiatives, but perhaps none is better remembered than his work on AIDS.

The disease was first identified in 1981, before Koop was officially in office, and it changed U.S. society. It destroyed the body's immune system and led to ghastly death, but initially was identified in gay men, and many people thought of it as something most heterosexuals didn't have to worry about.

U.S. scientists worked hard to identify the virus and work on ways to fight it, but the government's health education and policy efforts moved far more slowly. Reagan for years was silent on the issue. Following mounting criticism, Reagan in 1986 asked Koop to prepare a report on AIDS for the American public.